Uranus, the Original Ice Giant





Uranus is very cold and windy. It is surrounded by faint rings and more than two dozen small moons as it rotates at a nearly 90-degree angle from the plane of its orbit. This unique tilt makes Uranus appear to spin on its side.

Uranus is blue-green in color due to large amounts of methane, which absorbs red light but allows blues to be reflected back into space. The atmosphere is mostly hydrogen and helium, but also includes large amounts of water, ammonia and methane.

Astronomer William Herschel tried unsuccessfully to name his discovery Georgium Sidus after his patron, English king George III. Instead, the planet was eventually named for Uranus, the Greek god of the sky, who was also the father of Kronos (or Saturn in Roman mythology).









Quick facts about Uranus

Ice Giant
Uranus is about 4 times wider than Earth


Seventh Planet
Uranus is about 19.8 AU from the Sun, Earth = 1 AU


An Uranian Year
It takes Uranus 84 Earth years to make a trip around the Sun


Fluid Planet
Uranus is mostly a mass of "icy" fluid around a rocky core


Bring a Spacesuit
Atmosphere: molecular hydrogen and atomic helium with a bit of methane


Literary Moons
Uranus' 27 moons are named for characters in literature


13 Rings
Inner rings are dark; outer rings are brightly colored


Lonely Planet
Nasa's Voyager 2 is the only spacecraft to visit Uranus


No Signs
Uranus can't support life as we know it


East to West Rotation
Uranus is the only planet that rotates on its side